1. Technical Field
The present disclosure relates to an image forming apparatus and a process cartridge.
2. Description of the Related Art
An electrophotographic image forming apparatus, such as copier, printer, and facsimile machine, forms an electrostatic latent image on an image bearer and develops it into a visible image with a developer to obtain a recorded image. A dry developing device that uses powdery toner as the developer (or a part of the developer) is widely employed for use in electrophotographic image forming apparatuses.
Recently, full-color electrophotographic image forming apparatuses have been widely spread and digital images have become more easily available. In view of this situation, printed images are required to have higher definition.
To improve resolution and gradation of the images, various attempts have been made to make toner that visualizes electrostatic latent image have a spherical shape and a smaller particle diameter. Toners produced by pulverization methods have limitations in shape and size. On the other hand, toners produced by polymerization methods, such as suspension polymerization, emulsion polymerization, and dispersion polymerization, are capable of having a spherical shape and a small particle diameter.
In the cleaning process in electrophotography, a cleaner is generally used which is composed of a blade member formed of a platy urethane-rubber, etc., and a supporting member to which the blade member is attached in a longitudinal direction. One end of the blade opposite to the end attached to the supporting member is in contact with the surface of the image bearer at a predetermined pressure. The blade member slidably abrades the surface of the image bearer at a blade nip part formed therebetween while undergoing elastic deformation. As the surface of the image bearer is slidably abraded, toner particles or foreign substances remaining thereon are removed and collected. Such a method of cleaning image bearer is generally widely known as blade cleaning method.